Zavesca receives EU Marketing Authorisation

Zavesca, a capsule taken by mouth three times a day,
received European Commission approval on 26 November 2002 for the treatment of
patients with mild to moderate type 1 Gauchers disease for whom enzyme
replacement therapy is unsuitable. Patients taking the drug should be managed
by physicians knowledgeable about Gauchers disease.

Oxford GlycoSciences, which developed the drug following
pioneering work by Dr Fran Platt and Dr Terry Butters at Oxford
Glycobiology Institute, University of Oxford, has transferred marketing
authorisation to Actelion Ltd, a Swiss bio-pharmaceutical company. Actelion
began its launch of the drug in the UK on 3 March 2003.

As is usual for orphan drugs, the European Commission
has granted Zavesca marketing authorisation under exceptional circumstances,
requesting that follow-up safety data derived from a post-marketing
surveillance programme and additional clinical information is provided to the
authorities on a regular basis.

In a number of clinical trials, Zavesca was shown to
reverse many of the clinical signs and laboratory hallmarks of Gauchers
disease.

Zavesca (previously known as OGT 918) is a small
molecule drug which acts as an oral inhibitor of a key enzyme called
glucosylceramide synthase. The rationale for the use of the drug is to
help reduce the overall level of glycophingolipid (fatty material) which
accumulates in the spleen, liver, bone marrow and sometimes other places in
patients with Gauchers disease.

Surveillance Programme

During recent trials of OGT 918 (Zavesca) in Type 1
Gauchers disease, it was observed that most patients experienced
gastrointestinal disorders such as diarrhoea and flatulence, weight loss and
dizziness. Most of these resolved after a period of time.

In addition several patients had trembling and a few
developed a tingling, burning or numb sensation in their hands and feet. One
patient experienced memory loss but investigation indicated that this was
unlikely to be related to the drug.

The surveillance programme is aimed to find out more
about these latter symptoms. Patients taking the drug will be asked to undergo
a series of tests as given below.

In addition a number of adults with Gauchers disease who
are not taking Zavesca have been asked to participate in an
Observational Study. These are currently taking place in two Gauchers Centres,
one in the UK and one in Holland. Another UK Centre is due to participate
shortly.

Apart from routine assessments which are undertaken as
part of a six month routine follow-up, patients will be asked to take part
in:

Patients may be asked to repeat some of the tests at
regular intervals.

Advisory Council

The European Working Group on Gauchers Disease (EWGGD)
has established an Advisory Council of doctors, scientists and patient
representatives which has prepared a Position Paper including the criteria as to who would be
suitable candidates for the drug and what tests are necessary. The EWGGD will
also oversee the Observational Study.